Why voters prefer coalitions: Rationality or norms?

Abstract

This article asks if voters might prefer coalitions or single-party governments for ideological or normative reasons. Of course, they might prefer coalition to single-party governments for many reasons, one set clustering around the rational preferences of partisans largely in terms of expectations of electoral success or failure, and the other around the influence of norms or ideology. In terms of ‘rationality’, small-party supporters should want their party to have a role in government. Large-party supporters should prefer single-party government, unless their loyalties are weak, or unless they expect the large party they dislike will have the best chance of forming a government, and therefore hope that its power might be diluted by having to form a coalition. Meanwhile less partisan voters might or might not be influenced by norms that favour broadly based, consensual governments that command majority as compared to plurality support, that minimize parliamentary conflict, and that make it possible for successive governments to follow more consistent policies over time. Regardless of partisanship, some people might prefer strong governments, particularly if their disposition is authoritarian. Ideology might have effects independent of partisanship. Norms and preferences for type of government might also interact as part of change in a political culture. Using data from five elections that have generated coalition and/or minority governments in New Zealand, a country previously accustomed to single-party rule, this article tests these hypotheses and explores the implications of the findings.